Answer:
The general formula for the total surface area of a regular pyramid is T. S. A. =12pl+B where p represents the perimeter of the base, l the slant height and B the area of the base.
27; The first stack is 3 x 3 (= 9). You then multiply 9 by 3 (for each of the 3 stacks). Basically, 3 x 3 x 3.
X/-9 ≥3 multiply both side by -9 to get rid of fraction
-9/1•x/-9 ≥-9•3
Cross cancel -9 on left side
x ≥ -27
The total number of sandwiches Cassandra ordered is 150, however Cassandra is wrong, each guest will only get 3 sandwiches.